An ongoing investigation into the 2010 Enbridge oil spill by the U.S. National Transportation Safety Board is raising concern over frequent staff turnover and inexperience among personnel in the company’s Endmonton control-room.

Last Friday, the NTSB added new materials to the public accident docket, including transcribed interviews with Enbridge staff.

In the transcripts, one control-room operator likens his job to that of an air traffic controller and says he’d like to see Enbridge do more to retain control-room staff in the hot Alberta job market.

“And you just don’t have air traffic controllers coming in and out of the system like that, right, because you know that it will impact safety, right?” says the transcription. “So, I’d like to see them really look at keeping people in the control-room, keeping us happy in there, and I don’t know what it’s going to take, but that’s what I’d like to see.”

The employee added that when he started working at the company 25 years ago, he could count a combined 100 years of experience among four employees in the control-room. Now, he said, the experienced personnel in the room tend to only have three or four years under their belts.

The NTSB also reported that the time of the spill coincided with a shift change in the control-room, offering a possible explanation of why the spill went unnoticed for hours.

In a press release, Enbridge officials said that they would wait to comment on the new findings until the NTSB publishes its final report later this fall. In the release, officials added that the company been working to improve the safety of its operations in the two years since the spill by doing things like changing the “structure and leadership of functional departments such as pipeline control, leak detection and system integrity.”